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Rare Metals 2021年第8期40卷 2134-2142页

作者： Bao Wan Xiao-Qiang Li Cun-Liang Pan Dong-Yu Li Sheng-guan qu Chao Yang National Engineering Research Center of Near-Net-Shape Forming for Metallic Materials South China University of TechnologyGuangzhou510640China

For the purpose of elevated temperature service and weight reduction in aerospace vehicle applications,a novel Ti-Zr-Fe-Cu-Ni-Co-Mo filler metal was employed to join TiAl to Ni-based superalloy(GH536).The effects of brazing temperature on interfacial microstructure and chemical composition of the joints were *** representative joint microstructure from TiAl substrate to GH536 substrate was primarily composed of four characteristic layers in order:B_(2);Al_(3)NiTi_(2);AlNi_(2)Ti containing Cr-rich(Cr,Ni,Fe)_(ss)(subscript ss represents solid solution),Ni-rich(Ni,Cr,Fe)_(ss) and TiNi3;Cr-rich(Cr,Ni,Fe)_(ss)containing AlNi_(2)Ti,Ni-rich(Ni,Cr,Fe)_(ss) and *** IV has the majority of the brazing seam,while LayerⅡwas the *** the thickness of LayerⅡwas not affected by brazing *** the increase in brazing temperature in the range of 1110-1170℃,both the shear strength and the thickness of brazing seam firstly increased and then *** joint performance was jointly controlled by the thickness of brazing seam,the amounts of microcracks and intermetallic compounds formed in brazing *** maximum shear strength of 183 MPa at room temperature was obtained together with a peak thickness when the joint was brazed at 1150℃for 10 min and the shear fracture mainly occurred in the thinnest LayerⅡAl_(3)NiTi_(2).

关键词： TiAl alloy Ni-based superalloy Brazing Microstructure Shear strength

Wear Behavior and Mechanism of a Sliding Pair of 0.1C-3Cr-2W-V Nitrided Steel Rubbing against an Aluminum Bronze Alloy

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Journal of Iron and Steel Research International 2016年第3期23卷 281-288页

作者： guang-hong WANG Sheng-guan qu Zhi-hua XIONG Fu-qiang LAI Xiao-qiang LI Mao-sheng YANG School of Mechanical and Automotive Engineering South China University of Technology Institute of Special Steel Central Iron and Steel Research Institute

Wear behavior and mechanism of plasma nitrided steel oscillating against a heat-treated and an untreated aluminum bronze alloy were investigated using an Optimol SRV *** influence of heat treatment on the mechanical properties of the alloy was ***,the wear debris was also examined to understand the wear *** results show that a 220-230μm nitrided layer,which was harder than the substrate,was obtained on the steel *** tensile strength and hardness of the alloy are found to be significantly improved by the heat treatment associated with low impact *** heat treatment of the alloy did not obviously decrease the friction coefficient of the nitrided steel-bronze ***,the wear loss of the nitrided steel increased when it mated with the treated bronze by a severe three-body *** nitrided steel was mainly damaged by fatigue *** plane contact conditions,the wear debris was mainly generated from the bronze part and can escape from the interface before being oxidized,leading to the phase structure of all the debris being copper rather than copper oxides.

关键词： steel plasma nitriding aluminum bronze sliding wear three-body abrasion

Effect of short-time low-temperature austenitizing on microstructure and mechanical properties of DT300 ultra-high strength steel fabricated by laser powder bed fusion

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Journal of Iron and Steel Research International 2024年第7期31卷 1763-1777页

作者： Chen-yang Jiang Xiao-qiang Li Jin-tao Wang Hao Luo Sheng-qing Gao Sheng-guan qu Chao Yang National Engineering Research Centre of Near-Net-Shape Forming for Metallic Materials South China University of TechnologyGuangzhou 510640GuangdongChina Institute of New Materials Guangdong Academy of ScienceGuangzhou 510650GuangdongChina

To address the inhomogeneous microstructure and improve the mechanical properties of DT300 ultra-high strength steel specimens fabricated by laser powder bed fusion,different post-heat treatment schedules are *** the increase in austenitizing temperature and time,the migration rate of austenite grain boundaries continuously increases with the dissolution of nano-carbides,and the formation of nano-oxides and twin martensite is also inhibited *** rapid growth in the size of prior austenite grains and martensite laths,as well as the decrease in the content of nano-oxides and twin martensite,led to a rapid decrease in the strength(yield strength and ultimate tensile strength)from HT2 to HTF *** HT1 specimens(austenitizing at 830℃for 30 min,then oil quenching and tempering at 300℃for 120 min and finally air cooling)display excellent mechanical properties of yield strength of 1572 MPa,ultimate tensile strength of 1847 MPa,elongation of 9.84%,and fracture toughness of 106 MPa m^(1/2),which are counterparts to those of conventional DT300 steel forgings after heat treatment.

关键词： DT300 ultra-high strength steel Laser powder bed fusion-Short-time low-temperature austenitizing Microstructure Mechanical property

Microstructure and tribological properties of carburized 95W–3.5Ni–1.0Fe–0.5Co heavy alloy

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Rare Metals 2019年第2期38卷 165-172页

作者： Sheng-guan qu guang-Hong Wang Zhang-Xuan Yang Fu-Qiang Lai Zhi-Hua Xiong Hu Ke Xiao-Qiang Li School of Mechanical and Automotive Engineering South China University of Technology

Tungsten heavy alloys(WHAs) produced by powder technology are widely used for the mechanical manufacturing, electronic and defense components, *** properties of these alloys need to be improved to meet the severe service conditions demanded. Carburization is a promising way to resolve this problem. In this work, microstructure and tribological properties of the carburized 95W–3.5Ni–1.0Fe–0.5Co heavy alloy were investigated in comparison with those of the untreated alloy. Results show that the carburized layer consists of a porous, outer WC layer and a modified W grain layer surrounded by Fe_6W_6C and Co_6W_6C at 970℃, regardless of the carburizing time. The depth of the carburized layer linearly increases in a relatively short time and slightly increases during the subsequent period. Surface roughness increases with carburizing time. Carburization can stabilize friction coefficient and effectively improve the wear resistance of the tungsten heavy alloy due to its significantly increased hardness and non-deformability, but the porous structure in the WC layer has a negative influence on its wear resistance. The carburized layer is damaged in the porous WC layer in the form of the spalling of WC particles where there are some microcracks and micropores, accompanied with peeling due to the solid tribofilm being pushed away.

关键词： Tungsten: Carburization Surface roughness Wear Spalling

Novel Zwitterionic Surfactants: Synthesis and Surface Active Properties of N-(3-Alkoxy-2-Hydroxypropyl)-N, N-Dimethyl glycine Betaines

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Chinese Chemical Letters 1997年第6期8卷 499-502页

作者： Jing qu guan Xi You LI Chen Ho TUNG (Institute of Photographic Chemistry. Chinese Academy of Sciences. Beijing 100101) ACAD SINICA INST PHOTOG CHEMBEIJING 100101PEOPLES R CHINA

Five new zwitterionic surfactants with long chain alkyl betaine structure incorporated with hydroxylpropyl group have been synthesized. Their structures were identified by elemental analysis, IR (HNMR)-H-1, and (CNMR)-C-13. Surface tension experiments showed that these surfactants have higher surface activity than those without hydroxypropyl group. The values of CMC and gamma(CMC) of these surfactants have been determined.

关键词： ppm Synthesis and Surface Active Properties of N Novel Zwitterionic Surfactants OH OCH N-Dimethyl glycine Betaines Alkoxy-2-Hydroxypropyl

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我国草原退化加剧的深层次原因探析

内蒙古社会科学 2006年第4期27卷 1-6页

作者：王关区内蒙古社会科学院牧区经济研究所内蒙古呼和浩特010010

草原资源既是经济资源,更是生态资源,草原生态系统是我国第二大的生态屏障。然而,我国草原的退化沙化不断加剧,其生态防护功能和经济产出功能不断下降,特别是北方草原生态经济系统已出现恶性循环、逆行演替的态势。因此,深入分析草原退... 详细信息

草原资源既是经济资源,更是生态资源,草原生态系统是我国第二大的生态屏障。然而,我国草原的退化沙化不断加剧,其生态防护功能和经济产出功能不断下降,特别是北方草原生态经济系统已出现恶性循环、逆行演替的态势。因此,深入分析草原退化的原因,寻找治理改善草原生态环境的途径,推进草原生态经济良性循环、可持续发展,既有理论价值,更有现实意义。

关键词：草原退化加剧草原生态经济系统

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台车中深孔采矿中的测量方法研究

中国矿业 2016年第10期25卷 124-127页

作者：曲冠政山东黄金矿业(莱州)有限公司三山岛金矿山东莱州261400

普通双人操作型钻机进行中深孔采矿时,通常使用传统的测量方法。这种测量方法比较粗糙,炮孔定位和施工精度较低,会造成爆破孔分布不均或定位不准确,无法严格按照设计施工,容易导致爆破后出现超挖、欠挖、采场轮廓不规则等情况,甚至揭露F... 详细信息

普通双人操作型钻机进行中深孔采矿时,通常使用传统的测量方法。这种测量方法比较粗糙,炮孔定位和施工精度较低,会造成爆破孔分布不均或定位不准确,无法严格按照设计施工,容易导致爆破后出现超挖、欠挖、采场轮廓不规则等情况,甚至揭露F1冒落。本文针对台车中深孔采矿作业特点,提出了一整套创新的测量技术方案,在三山岛金矿中深孔采矿方法的试验中成功进行了应用,大大提高了现场作业的精度、效率和安全性,保证了中深孔采矿整体的施工质量和安全质量,并在后期爆破中取得了良好的爆破效果,在同行业其他矿山的生产中具有推广和借鉴意义。

关键词：中深孔台车测量方法上向扇形孔

Effect of carburization on microstructure and rolling contact fatigue property of 95W-3.4Ni-1.6Fe heavy alloy

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Transactions of Nonferrous Metals Society of China 2016年第12期26卷 3161-3169页

作者： guang-hong WANG Sheng-guan qu Rui-liang HE Ke HU Xiao-qiang LI National Engineering Research Center of Near-net-shape Forming Technology for Metallic Materials South China University of Technology Guangzhou 510640 China

95W?3.4Ni?1.6Fe heavy alloy was carburized by pack carburization. Microstructure and hardness of the carburized alloywere investigated by SEM, EDS XRD. Effect of carburization on the rolling contact fatigue (RCF) property of the alloy was *** results showed that the carburized layer was composed of the outer, porous WC layer and the modified subsurface layer witheach W grain surrounded by a WC shell. Carburization not only decreased the RCF performance of the alloy but also aggravated thewear of the counter balls. The untreated alloy was damaged by two modes of spalling and delamination under RCF condition. Thesubsurface main crack of the untreated alloy initiated where the maximum shear stress existed and preferentially propagated alongthe W?W interfaces. Spalling was the main failure mode of the carburized alloys, and the crumbling WC particles intensified theabrasion of the carburized surface.

关键词： tungsten alloy rolling contact fatigue carburization spalling

SPS循环热处理对93W-4.9Ni-2.1Fe与95W-2.8Ni-1.2Fe-1Al_2O_3合金组织及性能的影响

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中国有色金属学报 2018年第11期28卷 2224-2232页

作者：李小强刘波黄冠翔关模胡可屈盛官华南理工大学国家金属材料近净成形工程技术研究中心广州510641 华南理工大学金属材料高效近净成形技术与装备教育部重点实验室广州510640

利用放电等离子烧结(SPS)技术对具有相同理论密度的烧结态93W-4.9Ni-2.1Fe和95W-2.8Ni-1.2Fe-1Al_2O_3高密度钨合金进行循环热处理,并通过光学显微镜、SEM、TEM、EDS和三点弯曲实验分析循环热处理对两种合金显微组织和力学性能的影响规... 详细信息

利用放电等离子烧结(SPS)技术对具有相同理论密度的烧结态93W-4.9Ni-2.1Fe和95W-2.8Ni-1.2Fe-1Al_2O_3高密度钨合金进行循环热处理,并通过光学显微镜、SEM、TEM、EDS和三点弯曲实验分析循环热处理对两种合金显微组织和力学性能的影响规律。结果表明:随着SPS循环热处理次数的增加,93W-4.9Ni-2.1Fe合金在平均W晶粒尺寸未发生明显变化的同时,其粘结相中的W含量和位错密度不断升高,合金得到了固溶强化与位错强化,合金的硬度、抗弯强度、断裂挠度等性能相应提高;而对于95W-2.8Ni-1.2Fe-1Al_2O_3合金,由于更高的W含量和Al_2O_3颗粒的加入,烧结态时具有小得多的平均W晶粒尺寸、更大的W-W连接度和高硬脆特性,且SPS循环热处理对其组织和成分分布的均匀性影响程度相对较小,其力学性能虽然随SPS循环热处理次数的增加也得到了一定程度改善,抗弯强度和断裂挠度明显较93W-4.9Ni-2.1Fe合金的低,硬度则明显高于93W-4.9Ni-2.1Fe合金硬度。但循环热处理次数过多,反而会降低两种钨合金的硬度和断裂挠度。

关键词：高密度钨合金放电等离子烧结循环热处理组织性能

全面建成小康社会背景下内蒙古“三农三牧”发展路径研究

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内蒙古社会科学 2020年第3期41卷 207-212页

作者：王关区赵扬内蒙古社会科学院科研组织处内蒙古呼和浩特010010 首都经济贸易大学研究生院北京100070

解决好“三农三牧”问题是内蒙古如期实现全面小康的关键。新中国成立以来,内蒙古“三农三牧”发展取得了诸多成就,农牧业科技含量逐步增加,粮食总产量及单产大幅度提高,畜牧业综合生产能力显著增强,优势特色产业集群化发展,农牧民生活... 详细信息

解决好“三农三牧”问题是内蒙古如期实现全面小康的关键。新中国成立以来,内蒙古“三农三牧”发展取得了诸多成就,农牧业科技含量逐步增加,粮食总产量及单产大幅度提高,畜牧业综合生产能力显著增强,优势特色产业集群化发展,农牧民生活水平日益提升。尽管如此,以小农小牧经济为主体的格局还未从根本上改观,农牧业规模化集约化水平低、现代农牧服务业发展滞后、生产资金短缺等常态化问题仍然制约着“三农三牧”的进一步发展,这将严重阻碍如期实现全面建成小康社会的步伐。因此,需要尽快从根本上补齐这些短板,着力推进农牧业绿色、有机、特色化发展,有效延伸农牧业产业链,逐步健全优化农村牧区产业体系,有序开展乡村振兴“生态宜居”建设,构建高效的“三农三牧”经济制度体系。

关键词：内蒙古 “三农三牧” 成就短板